Morphology of Flowering Plants
Easy Overview
You see plants every day, but have you really looked at one? This chapter is about the outside of flowering plants — roots, stems, leaves, and flowers. After this, you'll never look at a mango tree the same way again.
The Root System
Roots anchor the plant and suck up water and minerals. There are two types: taproots (one big main root, like carrots) and fibrous roots (many thin roots, like grass). Taproots go deep. Fibrous roots spread wide. Some roots store food — that's what a radish is.
The Stem — The Plant's Highway
The stem holds the plant up and transports stuff between roots and leaves. Nodes are where leaves attach. Internodes are the gaps in between. Stems can be modified — potatoes are underground stems (tubers), not roots. Stem tendrils help climbing plants grab stuff.
The Leaf — The Food Factory
Leaves do photosynthesis. A leaf has a blade (the flat part), petiole (the stalk), veins (transport), and stomata (pores). Simple leaves have one blade. Compound leaves have multiple leaflets. Leaf arrangement on the stem can be alternate, opposite, or whorled.
The Flower — Nature's Marketing
Flowers are for reproduction. They attract pollinators with color and smell. Parts: sepals (protective outer), petals (attract pollinators), stamens (male part — makes pollen), pistil (female part — contains ovules). A complete flower has all four. Some flowers skip parts.
Inflorescence — Flowers in Groups
Sometimes flowers grow alone (solitary). Sometimes they grow in clusters — that's inflorescence. A sunflower isn't one flower — it's hundreds of tiny flowers packed together. Raceme, spike, umbel — these are different types of inflorescence patterns.
The Fruit and Seed
After pollination, the ovary turns into a fruit and the ovules become seeds. Fruits protect seeds and help disperse them. Mangos, apples, cucumbers — all fruits (yes, cucumbers are fruits botanically). A seed contains the embryo and stored food, waiting to grow.
Key Points
- •Taproot: one main root (dicots). Fibrous: many thin roots (monocots).
- •Stem: support and transport; nodes are leaf attachment points.
- •Leaf: blade, petiole, veins; does photosynthesis.
- •Simple vs compound leaves: one blade vs multiple leaflets.
- •Complete flower: sepals, petals, stamens, pistil.
- •Stamen = male part (anther + filament). Pistil = female part (stigma, style, ovary).
- •Fruit = mature ovary. Seed = mature ovule.
- •Inflorescence: how flowers are arranged on a plant.
Practice Questions
- Draw a labeled diagram of a typical flower.
- Differentiate between taproot and fibrous root.
- What is inflorescence? Describe any three types.
- Explain the structure of a leaf.
- Why is a potato considered a stem and not a root?